The present invention relates to an improved hermetically sealed rotary compressor.
Generally, rotary compressors produce less vibration and have a crank of shorter eccentricity as compared with reciprocating compressors, and therefore they are well suited to small-sized, hermetically sealed compressors. However, conventional hermetically sealed rotary compressors have had a cylinder block which is cut out considerably except for legs pressed into the internal wall of the sealed casing in order to curtail expenditure for raw material. Accordingly, the cutout has lowered the rigidity of most of the hermetically sealed casings, that is, except for the portion in which the cylinder block is force fitted, and has made noise louder. Thus, no sufficient countermeasures have been taken against noise (see U.S. Pat. No. 3,743,454).
Meanwhile, prior art hermetically sealed rotary compressors have been successfully miniaturized to some extent. Nevertheless, compressors of this kind have large overall heights, because such a compressor consists essentially of a vertically disposed hermetially sealed cylindrical casing cylinder, an electric motor force fitted in the casing in coaxial relation therewith and a rotary refrigerant compressing device disposed below the motor (see the above-cited U.S. Pat. No. 3,743,454). Consequently, air conditioners, freezers, refrigerators and so forth into which such a compressor is incorporated are difficult to manufacture compactly.
Accordingly, it is a principal object of the present invention to privide a small-size, low-noise compressor which has a lowered overall height yet has a capability comparable with those of conventional machines.